package com.example.filter;

import com.alibaba.fastjson.JSON;
import com.example.common.BaseContext;
import com.example.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.bind.annotation.DeleteMapping;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/*
* 检查用户是否已经完成登录
* */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
//@Component
public class LoginCheckFilter implements Filter {

    //路径匹配器,支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        //向上转型
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        //放行
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs",
                "**/favicon.ico"
        };
        //2.判断本次请求是否需要处理
        boolean check = check(urls,requestURI);
        //3.如果不需要处理，则直接放行
        if(check){
            filterChain.doFilter(request,response);
            return ;
        }
        //4-1判断登录状态，如果已经登录，则放行
        if(request.getSession().getAttribute("employee")!=null){

            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            long id = Thread.currentThread().getId();
            log.info("线程id为:{}",id);
            filterChain.doFilter(request,response);
            return ;
        }
        //4-2判断登录状态，如果已经登录，则放行
        if(request.getSession().getAttribute("user")!=null){

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            long id = Thread.currentThread().getId();
            log.info("线程id为:{}",id);
            filterChain.doFilter(request,response);
            return ;
        }
        //5.如果未登录返回未登录结果
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        //{}占位符
        log.info("拦截到请求：{}",request.getRequestURI());
        return;


    }

    /**
     * 路径匹配，检查本次请求是否放行
     * @param urls
     * @param requestURL
     * @return
     */
    public boolean check(String[] urls, String requestURL) {

        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURL);
            if (match) {
                return true;
            }
        }
        return false;

    }
}
